矩形断面综合管廊线缆舱通风阻力系数数值仿真研究

Numerical Simulation of Ventilation Resistance Coefficient of Utility Tunnel Cable Cabin with Rectangular Cross-section

为探究城市综合管廊通风阻力影响因素和计算方法,通过调研综合管廊通风系统设计和交通隧道通风阻力的相关研究成果,得到综合管廊线缆舱单位长度通风阻力系数的计算公式。建立综合管廊线缆舱三维数值模型,利用ANSYS FLUENT软件并采用标准双方程模型对通风障碍物比例约为15%的综合管廊线缆舱室内部支架、线缆和热效应对通风的阻力影响进行模拟。分析得到: 1)相较于内部无支架、线缆的综合管廊线缆舱,有支架、线缆时对通风阻力影响极大;2)随着通风风速的增大,综合管廊线缆舱通风阻力逐渐增大,而通风阻力系数减小,且逐渐趋于稳定;3)进口空气温度、线缆发热及舱内温度产生的热效应对通风的阻力效应有一定的影响,且随着进风温度增大,通风阻力和通风阻力系数逐渐降低。

In this paper, based on the relevant studies about the ventilation system design of utility tunnel and ventilation resistance of transportation tunnel, the calculation formula for the unit length ventilation resistance coefficient of the utility tunnel cable cabin is obtained. And then a 3D numerical model of the utility tunnel cable cabin is established, and the influence of the brackets, cables and thermal effect on the ventilation of the utility tunnel cable cabin with ventilation obstruction ratio of 15% is simulated by adopting the standard double equation model and software ANSYS FLUENT. The analysis shows that:(1) The brackets and cables have some significant influence on ventilation resistance of utility tunnel.(2) With the increase of the ventilation speed, the ventilation resistance increases while the resistance coefficient decreases to be stable.(3) The thermal effect of inlet air temperature, cable heating and cabin temperature have some effect on the ventilation resistance coefficient, and with the increase of inlet air temperature, the ventilation resistance and resistance coefficient decrease.